notifications@cinnamon.org - Avoid redundant update_list calls during clear all

[jsharpe1]

Problem

When clearing all notifications, each notification.destroy() triggers the destroy signal handler, which calls update_list() individually. With N notifications, this results in N+1 calls to update_list(), each recalculating urgency, updating icons/labels, reordering children, and requesting a relayout. When the notification count gets high, there is a noticeable hang when it clears all notifications. 50 notifications took 6.5 seconds to clear (see screenshot below).

Fix

Added a _clearing flag that causes the destroy handler to skip update_list() during bulk clear. The single update_list() call at the end of _clear_all() handles final state. Wrapped in try/finally to guarantee the flag resets if a destroy call throws.

Testing

Tested on Cinnamon 6.6.7 by triggering 50 notifications and clearing all. Verified via Looking Glass:

** Before: **

** After: **

Also verified:

• Clear all updates tray icon and count correctly
• Individual notification dismiss still updates the list

[fredcw]

what computer are you using? I have a 4 core ryzen3 and clearing 50 notifications takes about 150ms. There's a max of 20 notifications per app as well.

[jsharpe1]

@fredcw This is on my laptop - CPU is 11th Gen Intel(R) Core(TM) i7-11370H @ 3.30GHz.

Out of curiosity, I ran the same test (generating 50 notifications and clearing all) on my desktop, and did not have the same performance issue. That's running a 13th Gen Intel(R) Core(TM) i5-13600KF.